46 AMERICAN AGRICULTURE. 



25 bushels per acre. They may be repeated in less quanti- 

 ties every four or five years, or till the soil ceases to be im- 

 proved by them, when they should be withheld till addition- 

 al cropping shall have so far exhausted them, as to justify a 

 further application. 



Bones are generally boiled before using for manure, to 

 extract the oil and glue. This does not lessen their value 

 for agricultural purposes, beyond the diminution of their 

 weight, while it hastens their action. They are sometimes 

 burned, which drives off all the organic matter, leaving only 

 the lime and other bases, to benefit the soil. This is a 

 wasteful practice, though the effect is more immediate on the 

 crops ; but it is also more transient, and they require to be 

 more frequently renewed. 



Bones ought always to be saved ; and if not practicable 

 to crush them, they may be thrown upon the land, where 

 they will gradually corrode and impart their fertilizing pro- 

 perties. When partially decomposed and buried just beneath 

 the surface, the roots of the luxuriant plants above, will 

 twine around them in all directions, to suck out the rich food 

 which ministers so freely to their growth. Crushed bones 

 are advantageously used with nearly an equal amount of 

 ashes, or with one third their weight of gypsum ; or they 

 may very properly, be added to the muck heap, where de- 

 composition will be hastened, and they will sooner be pre- 

 pared to impart all their fertility to the crops. 



The effect of ground bones is greatly hastened and aug- 

 mented by dissolving them in sulphuric acid. This is done 

 by placing the bones in tight casks or large kettles, and then 

 adding one third their weight of acid, diluted with half its 

 weight of water. This mixture immediately raises the tem- 

 perature to 300 Far., and decomposition of the bones soon 

 results. Then add to this product, two or three times its 

 bulk of light mold, and when dried, it may be drilled in with 

 the seed by a machine, or scattered broadcast. Or a heap 

 of fine mold may be formed like a basin, the bones thrown 

 into the centre and the diluted acid added ; when dissolved 

 all may be mixed together. The whole nutritive matter 

 contained in the bones, is thus .set free for the use of the 

 plants, which would otherwise require years to accomplish, 

 from the great insolubility of bones. Less than one fourth 

 the quantity usually applied, will thus be equally beneficial 

 for the first season, though the prolonged effects of the larger 

 quantity will be greater*. 



